KRACOEUS-8181: convenient way to clear pessimistic locks to make it easi...

...er for testing.
When I'm saying lenient I generally mean about not found status.  So if a user clicks the link twice you could do one of two things for the second click: 1) return a 404 or two return a 200 type status.  Now if you return a 404 for the second click then the DELETE is not idempotent.  So from what I've read, it is many time acceptable to return a 200 code even when the resource you are deleting does not exist.

As for other conditions, I could probably return a 500 error.  Either way this is a good discussion because it would e good to start thinking about how best to handle DELETEs and not found conditions.